The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 29, 1980
Filed:
Nov. 16, 1977
Applicant:
Inventors:
Mitsuo Hasebe, Tokyo, JP;
Mutsuo Watanabe, Tokyo, JP;
Kunio Hibi, Tokyo, JP;
Masayosi Watanuki, Tokyo, JP;
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03G / ;
U.S. Cl.
CPC ...
355 / ; 118712 ; 222D / ; 324200 ;
Abstract
A toner mixture comprising ferromagnetic carrier particles and non-magnetic toner particles are caused to flow through a conduit for measuring the toner density which is the ratio of toner particles to carrier particles in the mixture. The effective inductance of an electromagnetic coil disposed in the conduit varies in accordance with toner density. The coil is designed so that the magnetic lines of force thereof are substantially confined within the conduit and are not influenced by external bodies.